• Conservation Science in Museum
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• v.12
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• pp.1-7
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• 2011

The seated stone Buddha(Bon5190) of National Museum of Korea initially consisted of some 90 fragments, making it difficult to guess its overall appearance. Under a restoration work which lasted four months, the fragments were joined together, giving shape to a seated Stone Buddha in Bhumisparsa(earth touching) mudra and an associated figure of Bodhisattva missing the face. The statue was made from a single stone block by digging out the center. Traces of lacquer coating and a gilded layer above the lacquer coat were found in various parts. Polarizing microscopy and XRD analysis revealed that the stone was zeolite, a mineral formed through diagenesis of volcanic glassy ashes from trachytic tuff (Nuldaeri) and dacitic tuff (Guryongpo). In Korea, zeolite deposit found mostly in Gyeongsangbuk-do, in places like Yeonil, Guryongpo, Gampo and Ulsan. The restored statue of seated Buddha proved very similar in appearance to the seated stone Buddha of Deoksa Temple in Cheongdo-gun, Gyeongsangbuk-do (housed in Yeongsanjeon Hall). The scroll inside the statue, containing information about the background and circumstances of creation of this Buddhist sculpture, indicates that the monk Seung-ho took part in it as the head sculptor-monk.

• The Journal of the Petrological Society of Korea
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• v.11 no.3_4
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• pp.169-181
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• 2002

Basic~intermediate dike swarms are pervasively developed in the east of the Ulsan Fault, SE Korea. Most of them intruded initially along the NS-trending extensional fractures which developed under EW extension during the East Sea opening in the Early Miocene (before about 17 Ma). The mean-strikes of the basic dikes intruding into the granites are more clockwise rotated in farther eastern side, i. e.$ N06^{\circ}$E, $Nl5^{\circ}$E, and $N37^{\circ}$E in the western side, in the just vicinities, and in the eastern side of the YBonil Tectonic Line (YTL), respectively. And the mean-strike of the basic dikes nearby shoreline is also most clockwise rotated ($N75^{\circ}$E in the Guryongpo Peninsula). The spatial variance indicates that the dikes, located only in the east of the YTL, experienced horizontal-clockwise rotation, and that the dikes in farther east from the YTL experienced more clockwise rotation. It is, thus, supported that the NNW dextral shear stress, generated by the spreading of the East Sea, was propagated toward inland from eastern continental margin of the Korean Peninsula, and that the YTL is an westernmost limit of the clockwise crustal rotations which are pervasively observed in the vicinities of the Miocene basins, SE Korea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.4
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• pp.341-348
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• 1983

The Relationship between the distribution of the fishing grounds of anchovy and the oceanographic conditions in the Korean Waters are investigated by using the data of the catch of anchovy by the gill net fishery (Fisheries Research and Development Agency, 1969-1982) and the oceanographic observation data (Fisheries Research and Development Agency, 1979). The main fishing ground of anchovy by the gill net fishery was five fishing areas located in the adjacent seas of Sockcho, Kuryong-po, Kijang, Keoje island and Chungmu, the area of which occupies no more than $20\%$ of all fishing grounds, and it appeared that about $80\%$ of mean catches of fourteen years was concentrated in this area. The main fishing periods were from April to June and October to November. The coefficient of variation of the catch for the main fishing ground were from 0.3 to 0.6 and the condition of all fishing ground was generally stable. The mean CPUE was 81.2 kg/set at the main fishing ground. The annual mean catch of anchovy by the gill net was the smallest in February and the largest in May through a year. It was found that the fluctuation is related to the expansion and reduction of the isothermal line of $10^{\circ}C$.

• Korean Journal of Environmental Biology
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• v.30 no.4
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• pp.355-361
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• 2012

Genus of Gambierdiscus, Ostrepsis, Prorocentrum, Coolia and Amphidinium are epiphytic ciguatoxin-producing armored dinoflagellate, often attached on macroalgae. These organisms are the primary causative agent of ciguatera fish poisoning which occurs in tropical and subtropical regions. However, regardless of the fact that population of epiphytic dinoflagellates have expanded to such temperate areas from sub-trophic and trophic areas, monitoring of the epiphytic dinoflagellates was greatly lacked in coastal water of Korean Peninsula. This study was performed in the Korean Peninsula in November, 2011. Cell densities of Gambierdiscus spp. on macroalgae ranged from zero to 10 cells $g^{-1}$ and the maximum density was recorded at St.18 (Pohang guryongpo). The abundance of Ostreopsis spp. was highest on macro-algaes Chondrus ocellatus, Lomentaria catenata and Plocamium telfairiae (140 cells $g^{-1}$). The maximum abundance of Prorocentrum, Coolia and Amphidinium were 52, 3 and 1 cells $g^{-1}$, respectively. Of these, Prorocentrum lima was observed at most stations of East Sea. Therefore, our results suggest that the epiphytic armored dinoflagellates may have adapted to Korean coastal water of temperate areas (i.e., East Sea) and those abundances may be related to the macroalgal species.

• Economic and Environmental Geology
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• v.37 no.2
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• pp.245-253
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• 2004

The 36km-long Daebo-Campo coast has a well-developed marine terraces divided to six steps by elevation of paleoshoreline : 0.5 m(T1), 10 m(T2), 30 m(T3), 40 m(T4), 60 m(T5) and 75 m(T6). The 2$^{nd}$ and 3$^{nd}$ platforms in Daebo to Guryongpo are wider and more distinctive than those of Guryongpo to Gampo. The 3$^{nd}$ terrace of 30 m high is subdivided to two flights as lower(T3b) and upper(T3a) by old sea cliff. Platform age is unclear because of coral fossil free. However, the terrace age could be determined with convergent OSL ages from beach sediments on 2$^{nd}$ step(T2). OSL ages of the terrace of 10 m high range in 60-70 ka. It reveals that the 2$^{nd}$ -step platform correlates to Oxygen Isotope Time scale, substage 5a(ca. 80 ka), and that uplift rate is ca. 0.19 m/ka for 2$^{nd}$ terrace at Daebo-Campo coast. If considering equivalent uplift rate for all terraces since the Late Pleistocene, the 3$^{rd}$ and 4$^{th}$ terraces would be 5e substage and 7 stage. The 30 m-high terrace provides a good indicator for uplift at Daebo-Gampo coast since 125,000 yrs(MIS 5e). It suggests that the local neotectonic deformation might cause an optional uplift rate of ca. 0.19 m/ka along the SE coast of Korea.

• Economic and Environmental Geology
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• v.19 no.3
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• pp.231-237
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• 1986

Samples of porphyries, andesites, decites and sandstones were collected from 14 sites in order to study paleomagnetism and to determine K-Ar age in Guryongpo area. K-Ar age dating indicates that porphyries and volcanic rocks formed 41.7 and 22.7~19.4Ma, respectively. The mean direction of remanent magnetization for each site was generally well grouped after alternating field demagnetization. Both normal and reversed directions are present. The mean magnetic direction of the porphyries of Late Eocene and that of the volcanic rocks of Late Oligocene to Early Miocene have similar, easterly declinations. Overall magnetic direction is $Dm=43.8^{\circ}$, $Im=53.5^{\circ}$, ${\alpha}95=12.2^{\circ}$. the reliability of the observed paleomagnetic directions is ascertained by the presence of normal and reversed polarities. This is also conformed by the similarity of the declinations of the normal and reversed polarities. Observed easterly declinations in this area are attributed to local clockwise rotation of the land mass by approximately 40~50 degrees since early Miocene.

• Korean Journal of Remote Sensing
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• v.39 no.6_1
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• pp.1235-1243
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• 2023

This study proposes the detection algorithm for the cold water mass (CWM) along the eastern coast of the Korean Peninsula using sea surface temperature (SST) data provided by the Korea Institute of Ocean Science and Technology (KIOST). Considering the occurrence and distribution of the CWM, the eastern coast of the Korean Peninsula is classified into 3 regions("Goseong-Uljin", "Samcheok-Guryongpo", "Pohang-Gijang"), and the K-means clustering is first applied to SST field of each region. Three groups, K-means clusters are used to determine CWM through applying a double threshold filter predetermined using the standard deviation and the difference of average SST for the 3 groups. The estimated sea area is judged by the CWM if the standard deviation in the sea area is 0.6℃ or higher and the average water temperature difference is 2℃ or higher. As a result of the CWM detection in 2022, the number of CWM occurrences in "Pohang-Gijang" was the most frequent on 77 days and performance indicators of the confusion matrix were calculated for quantitative evaluation. The accuracy of the three regions was 0.83 or higher, and the F1 score recorded a maximum of 0.95 in "Pohang-Gijang". The detection algorithm proposed in this study has been applied to the KIOST SST system providing a CWM map by email.

• Journal of the Mineralogical Society of Korea
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• v.16 no.2
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• pp.135-149
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• 2003

Domestic zeolite ores are mostly composed of Ca-type clinoptilolite, accompanying a little amounts of mordenite. However, other types of zeolite ores rich in ferrierite, heulandite, or mordenite are less commonly found. Based on the quantitative XRD analysis, zeolite contents are determined to be nearly 50∼90 wt%. Impurities (mostly ＞ 10 wt%) in the zeolite ores chiefly consist of quartz, feldspar, smectite, and opal-CT. The determined CEC values ($CEC_{AA}$ ) of powdery samples (grain size: < 125 $\mu\textrm{m}$) of zeolite ores by the Ammonium Acetate method are mostly higher than 100 meq/100 g. Some zeolites from the Guryongpo area, corresponding to the clinoptilolite ore, are measured to be dominantly high in CEC values ranging 170∼190 meq/100 g. Cation exchange property of the zeolite ores varies greatly depending on the types or zeolite species present in the ores. Despite of the lower grade in zeolite content, the $CEC_{AA}$ of ferrierite ore is comparatively high. Compared to this, the $CEC_{AA }$ of heulandite ore is very low, though the zeolite ore exhibits the highest grade ranging up to about 90 wt%. In addition, the CEC values calculated theoretically from the framework composition of clinoptilolite-heulandite series are not consistent with those determined by the cation exchage experiment. The measured $CEC_{AA}$ of clinoptilolite ores are generally higher than those of heulandite ores. This may be due to the higher Ca abundance in exchangeable cation composition and the presence of probable stacking faults in heulandite. The variation of $CEC_{CEC}$ is roughly proportional, though not strictly compatible, to the zeolite contents in clinoptilolite ores. It seems to be caused by the fact that the $CEC_{AA}$ of clinoptilolite locally varies depending on crystal-chemical diversity, i. e., the variation in framework composition (Si/Al) and exchangeable cation composition (especially, the contents of Ca and K). In addition, the determined CEC values ($CEC_{MB}$ ) of zeolite ores by the Methylene Blue method are much higher than those calculated from smectite contents. It suggests a probable reaction of Methylene Blue ion ($C_{16}$ $H_{18}$ $N_3$S+) with larger-pore zeolites than clinoptlolite-heulandite series, i.e., ferrierite and mordenite as well as with smectite. This can be supported by the fact that the ferrierite ore accompanying little amount of smectite has the highest value in CE $C_{MB}$ .

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.2
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• pp.92-100
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• 1984

The seasonal variation of catch and the fishing ground formation of anchovy caught by gill net are studied by using the data for 14 years, 1969 to 1982, published by the Fisheries Research and Development Agency of Korea. The main fishing season of anchovy by gill net can be devised into two seasons: spring and autumn. The former begins early in spring, marks peak in May with the monthly mean catch of 3,000 $\frac{M}{T}$ and ends in summer. The latter begins early in autumn, marks peak in October with the monthly mean catch of 1,500$\frac{M}{T}$ and ends in winter. The fishing ground begins to be formed in the southern waters of Korea with the begining of spring fishing season, and it is extended all over the south-eastern waters from spring to summer and it is converged to the coastal areas from autumn to winter. From the calculation of correlationship between adjacent fishing sections, the fishing ground can be devided into three areas; the northern area of $37^{\circ}N$, the southern area of $35^{\circ}N$ and the area between $35^{\circ}N\;and\;37^{\circ}N$. In the northern area of $37^{\circ}N$, monthly centers of the fishing ground are located in the adjacent aea area of Sockcho-Jumunjin district in the whole year, and its annual mean variance shows about 8 miles in the latitudinal direction and 10 miles in the longitudinal direction. In the area between $35^{\circ}N\;and\;37^{\circ}N$, monthly centers are located in the adjacent sea area of Kijang-Kuryongpo district, and the variance shows about 10 miles in the longitudinal direction and 20 miles in the latitudinal direction. In the southern area of $35^{\circ}N$, monthly centers are located in the open sea in spring and summer, and are conversed to the coastal area in autumn and winter, and the variance shows 8 miles in the latitudinal direction and 35 miles in the longitudinal direction. Water temperature and salinity at the fishing ground where the anchovy gill net was effectively operated are estimated from 14 to $20^{\circ}C$ and from 33.0 to $34.0\%0$ respectively.